The Human Assessment and Biostatistical Core (HABC Core) will play an integral role as part of the proposed Special Center of Research in Neurobiology of Sleep and Sleep Apnea. The Core's specific aims (functions) are: 1) to provide innovative biostatistical solutions to data analysis challenges arising from clinical and basic science SCOR projects; 2) to provide centralized statistical programming and data management resource to the human projects (Projects 01 and 05) and the animal clinical trial component of Project 03 and to implement non-routine statistical methodology for Project 04 (adenosine); 3) to research, develop, and assess the utility of new and existing: a) human assessment instruments, b) measurement modalities, and c) follow-up strategies; and 4) to maintain and expand the Clinical Research Support Data Base (CRSD) to facilitate subject recruitment and to provide a means for methodological and technology transfer. The Clinical Research Support Data Base (CRSD) is a multi-center patient registry used in a number of distinct but inter-related ways. Its four primary functions are: 1) to help in the process of screening patients for inclusion and exclusion criteria for Projects 01 and 05; 2) to support the human projects by providing access to demographic information, symptom reports, physical assessments, and results from overnight polysomnography for all study participants; 3) to support the human projects by providing access to a large population for psychometric evaluation of existing and new measurement instruments, and to facilitate ancillary analyses; 4) to foster technology transfer of research results into clinical practice. Core C puts together an experienced data analysis team including a biostatistician with extensive experience collaborating with Project Leaders, a senior statistical programmer, data manager, and data clerk all using state-of-the-art statistical software (SAS/TM). The Core will serve as the primary mechanism of the implementation of statistical analyses of data arising from Project 01 and Project 05, from the clinical trial component of Project 03, and will implement the harmonic regression analyses for Project 04 as well as provide biostatistical to all Projects.